1. Field of the Invention
The present invention relates generally to a method and system for controlling the operation of an Anti-lock Brake System (ABS) and, more particularly, to a method and system for controlling the operation of an ABS, which reduces a loss of gas mileage by efficiently removing motor torque by detecting the operation of the ABS more accurately.
2. Description of the Related Art
For a hydraulic brake, the braking of a vehicle is performed by braking hydraulic pressure applied from a master cylinder when a brake pedal is engaged. When braking power greater than static friction force between a road surface and tires is applied to the tires, a slip phenomenon, that is, a phenomenon in which the tires slide on the road surface, is generated. To prevent such a phenomenon and maintain stable braking power, an ABS has been developed. An ABS detects a slip phenomenon and adjusts braking hydraulic pressure based on the detection to stop a vehicle within the shortest distance. An ABS may include an (electronic control unit) ECU that operates electrical elements and hydraulic control devices, such as a plurality of solenoid valves, an accumulator, and a hydraulic pump that adjusts braking hydraulic pressure transferred to hydraulic brakes. In general, a slip value is calculated based on wheel speed detected by sensors and vehicle speed estimated from the wheel speed, and an ABS operates when the calculated slip value reaches a predetermined slip value.
For an electric vehicle or a fuel cell vehicle, when rapid braking is performed with substantially low friction, noise and wheel vibration are generated in a driving motor when an ABS initially operates. because the noise and wheel vibration is generated since unlike in an engine vehicle using an automatic transmission, the driving motor, a decelerator, and wheels are directly connected without a hydraulic transmission, the driving motor leans toward a regenerative braking direction due to a coast regenerative braking action (which performs a function similar to that of an engine brake) prior to braking, and a shock is applied to the driving motor since braking power is suddenly changed due to a sudden reduction in braking hydraulic pressure when the ABS is operated while force attributable to inertia during rapid braking is applied in the direction of driving.